BINARIES MIGRATING IN A GASEOUS DISK: WHERE ARE THE GALACTIC CENTER BINARIES?
BINARIES MIGRATING IN A GASEOUS DISK: WHERE ARE THE GALACTIC CENTER BINARIES?
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DOI：
10.1088/0004-637x/726/1/28
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发表时间：
2010-11
期刊：
影响因子：
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通讯作者：
C. Baruteau;J. Cuadra;D. Lin
中科院分区：
文献类型：
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作者：
C. Baruteau;J. Cuadra;D. Lin
银河系中心内弧秒的大质量恒星与所谓的热彗星具有类似的性质。这些年轻的恒星大多数都有高度偏心的轨道，可能不是在原地形成的。有人提出，这些恒星获得了它们目前的轨道从潮汐破坏紧凑的大质量双星分散到中央超大质量黑洞附近。假设一个二元星星形成于一个薄的气体盘超过0.1 pc的中心对象，我们调查的相关性磁盘卫星相互作用硬化的结合能的二进制，并推动其向内迁移。一颗质量相等的大质量双星星星在向中心黑洞迁移时，被发现缠绕得更紧。迁移时间尺度与相同质量的单星卫星非常相似。双星的硬化是由于在希尔半径内的恒星后面形成了螺旋尾巴。我们表明，硬化时标主要是由二进制的希尔半径内的气体的质量，它是远远短于迁移时标。我们讨论了一些影响的二进制的硬化过程。当密近双星中质量较大的（主）成分通过超新星爆炸喷射出大部分质量时，它们的副恒星可能会达到一定的偏心率和倾角。这样的过程可能会提供一个替代的统一方案的起源的运动学性质的中央集群和S-星在银河系中心，以及在银河系晕的高速恒星。
The massive stars in the Galactic center inner arcsecond share analogous properties with the so-called Hot Jupiters. Most of these young stars have highly eccentric orbits and were probably not formed in situ. It has been proposed that these stars acquired their current orbits from the tidal disruption of compact massive binaries scattered toward the proximity of the central supermassive black hole. Assuming a binary star formed in a thin gaseous disk beyond 0.1 pc from the central object, we investigate the relevance of disk–satellite interactions to harden the binding energy of the binary, and to drive its inward migration. A massive, equal-mass binary star is found to become more tightly wound as it migrates inward toward the central black hole. The migration timescale is very similar to that of a single-star satellite of the same mass. The binary's hardening is caused by the formation of spiral tails lagging the stars inside the binary's Hill radius. We show that the hardening timescale is mostly determined by the mass of gas inside the binary's Hill radius and that it is much shorter than the migration timescale. We discuss some implications of the binary's hardening process. When the more massive (primary) components of close binaries eject most their mass through supernova explosion, their secondary stars may attain a range of eccentricities and inclinations. Such processes may provide an alternative unified scenario for the origin of the kinematic properties of the central cluster and S-stars in the Galactic center as well as the high-velocity stars in the Galactic halo.